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This is a mean question

Arthur's twin sisters are 4 years older than him. Altogether their ages add up to 77. How old is Arthur?
Reply 1
Original post by ChaitraS
Arthur's twin sisters are 4 years older than him. Altogether their ages add up to 77. How old is Arthur?

23
Reply 2
Let Arthur’s age = a, let the twin sisters age = t ….
Reply 3
so
lets do it algebraically
Arthur = X
each twin therefore must = X + 4 ( Arthurs age plus 4)
and because there's two of them it would be 2x + 8. (X + 4 but in two lots)
SO
putting it all into an equation it would be,
X + 2x + 8= 77

we minus the 8 to equal 69
so 3x = 69
/ both by 3
x= 23
and obvs the twins would 27
(edited 2 months ago)
Original post by ChaitraS
Arthur's twin sisters are 4 years older than him. Altogether their ages add up to 77. How old is Arthur?

i would use simultaneous equations, so say that arthur is a and the twins are each t, you can use the equations:
t-a=4
2t+a=77
then add the equations together so that -a and a cancel out, so you get
3t=81
t=27
then plug 27 into the first equation, so
27-a=4
a=23

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